The notion that 3663.5km of riding a bike within a three week period might affect the human the body should hardly come as a surprise, but a photo posted by Polish cyclist Bartosz Huzarski's legs taken after the 18th stage of the Tour de France highlighted just how great a toll the event places on its athletes.

The striking image led to some questioning whether Hubarski had dabbled in blood doping, claims which he dimissed on his Facebook page.

"I did not expect that picture of my legs would cause the confusion it did," he said.

"Of course I will not have legs like Victoria’s Secret models, or Mary from a nearby vegetable shop, or anyone working in an office who does a 10km bike ride or an hour run three times a week. Unfortunately it does not work like that and this what you see in the picture. It is not unhealthy."